Effect of controlled pointlike disorder induced by 2.5-MeV electron irradiation on the nematic resistivity anisotropy of hole-doped (Ba,K)Fe2As2
| Autor: | Kyuil Cho, Yong Liu, olivier cavani, Marcin Konczykowski, Ruslan Prozorov, Makariy A. Tanatar, Erik I. Timmons, Thomas A. Lograsso |
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| Rok vydání: | 2020 |
| Předmět: | |
| Zdroj: | Physical Review B. 102 |
| ISSN: | 2469-9969 2469-9950 |
| DOI: | 10.1103/physrevb.102.144511 |
| Popis: | In-plane anisotropy of electrical resistivity was studied in samples of the hole-doped ${\mathrm{Ba}}_{1\ensuremath{-}x}{\mathrm{K}}_{x}{\mathrm{Fe}}_{2}{\mathrm{As}}_{2}$ in the composition range $0.21\ensuremath{\le}x\ensuremath{\le}0.26$ where anisotropy changes sign. Low-temperature ($\ensuremath{\sim}20$ K) irradiation with relativistic 2.5 MeV electrons was used to control the level of disorder and residual resistivity of the samples. Modification of the stress-detwinning technique enabled measurements of the same samples before and after irradiation, leading to the conclusion of anisotropic character of predominantly inelastic scattering processes. Our main finding is that the resistivity anisotropy is of the same sign irrespective of residual resistivity, and remains the same in the orthorhombic ${C}_{2}$ phase above the reentrant tetragonal transition. Unusual $T$-linear dependence of the anisotropy $\mathrm{\ensuremath{\Delta}}\ensuremath{\rho}\ensuremath{\equiv}{\ensuremath{\rho}}_{a}(T)\ensuremath{-}{\ensuremath{\rho}}_{b}(T)$ is found in pristine samples with $x=0.213$ and $x=0.219$, without similar signatures in either ${\ensuremath{\rho}}_{a}(T)$ or ${\ensuremath{\rho}}_{b}(T)$. We show that this feature can be reproduced by a phenomenological model of R. M. Fernandes et al. [Phys. Rev. Lett. 107, 217002 (2011)]. We speculate that onset of fluctuations of nematic order on approaching the instability towards the reentrant tetragonal phase contributes to this unusual dependence. |
| Databáze: | OpenAIRE |
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